Frequently embossing rolls are associated with printing presses and are used to emboss successive areas of a paper strip or other films, including plastic or aluminum foil for producing three dimentional effects on a finished printed roll of labels or the like. The patented art cited above shows a typical embossing roll station adapted to cooperate with a printing press. When a line of printed material is to be embossed, the bearing mountings for the embossing rolls are built into the press line and the rollers are driven to rotate in precise sequence to the operation of the printing means so that the desired embossing of the areas that are to be made three dimensional, can be coordinated with a printed label run for example. The resulting line of printed and embossed labels can then be rolled up for delivery to the ultimate user.
From time to time the pair of embossing rolls on a press line must be replaced, and particularly in a job shop printing activity, where different customers make use of embossed label designs, the embossing rolls at the embossing station must be changed with each press run. When a changeover is being made, in following current practice, it is necessary to tie up the entire press line, and because of the extreme care that is required to effect the necessary precision required in mounting the new pair of embossing rollers in order to coordinate the embossed design with the printed matter, the down time consumed in making a change over and the time spent by skilled press operators in such labors, makes the replacement of embossing rolls a relatively costly procedure.
Embossing rolls have matching three dimensional contoured peripheries, one of the peripheries being a male protrusion and the other a corresponding matching female depression. The rolls are usually formed integrally with bearing shafts that are intergeared so that the peripheral surfaces of the rollers rotate into opposed positions precisely matching one another to emboss the material being passed between the rolls. Not only must the embossing station be positioned precisely relative to the printing press but the embossing rollers themselves must be positioned at their station to coact properly one with the other to produce the desired embossed design in the exact position required on the printed line of labels or the like issuing from the printing press. Depending upon their design, certain of such rollers can be quite heavy, thus necessitating extreme care in handling to avoid any damage to their embossing die surfaces while being fitted into the press line. Thus at the properly located embossing station of conventional printing presses, the embossing rolls, some of which may be difficult to manipulate into place, must be carefully aligned both longitudinally and latterally to rotate precisely relatively to each other and the matched rollers must also be adjusted to coact with the line of printed matter, which of course, necessitates that they must also be rotated to a precise position.
All of the adjustments required to be made to fit the individual embossing rolls into their respective bearing supports in a press line, require expert attention by skilled pressmen and precise adjustments that must be completed on the part of these press operators. For this reason and because the entire printing printing press line must remain inactive while the removal of one set of embossing rolls and the fitting of the new set of rolls is accomplished, it is apparent that any speed-up of the change-over procedure is much to be desired.